diff options
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp | 7 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/opaque.ll | 32 |
2 files changed, 39 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp index 80b138e8c36..dddcd0183b3 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp @@ -1922,6 +1922,13 @@ Instruction *InstCombiner::visitBitCast(BitCastInst &CI) { if (Instruction *V = PromoteCastOfAllocation(CI, *AI)) return V; + // When the type pointed to is not sized the cast cannot be + // turned into a gep. + Type *PointeeType = + cast<PointerType>(Src->getType()->getScalarType())->getElementType(); + if (!PointeeType->isSized()) + return nullptr; + // If the source and destination are pointers, and this cast is equivalent // to a getelementptr X, 0, 0, 0... turn it into the appropriate gep. // This can enhance SROA and other transforms that want type-safe pointers. diff --git a/llvm/test/Transforms/InstCombine/opaque.ll b/llvm/test/Transforms/InstCombine/opaque.ll new file mode 100644 index 00000000000..f2a91855d5a --- /dev/null +++ b/llvm/test/Transforms/InstCombine/opaque.ll @@ -0,0 +1,32 @@ +; RUN: opt < %s -instcombine -disable-output +; Checks that bitcasts are not converted into GEP when +; when the size of an aggregate cannot be determined. +%swift.opaque = type opaque +%SQ = type <{ [8 x i8] }> +%Si = type <{ i64 }> + +%V = type <{ <{ %Vs4Int8, %Vs4Int8, %Vs4Int8, %Vs4Int8, %Vs4Int8, %Vs4Int8, %Vs4Int8, %Vs4Int8 }>, %Si, %SQ, %SQ, %Si, %swift.opaque }> +%Vs4Int8 = type <{ i8 }> +%swift.type = type { i64 } + +declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, +i64, i32, i1) #8 + +@_swift_slowAlloc = external global i8* (i64, i64)* + +declare i8* @rt_swift_slowAlloc(i64, i64) + +define %swift.opaque* @_TwTkV([24 x i8]* %dest, %swift.opaque* %src, +%swift.type* %bios_boot_params) #0 { +entry: + %0 = bitcast %swift.opaque* %src to %V* + %1 = call noalias i8* @rt_swift_slowAlloc(i64 40, i64 0) #11 + %2 = bitcast [24 x i8]* %dest to i8** + store i8* %1, i8** %2, align 8 + %3 = bitcast i8* %1 to %V* + %4 = bitcast %V* %3 to i8* + %5 = bitcast %V* %0 to i8* + call void @llvm.memcpy.p0i8.p0i8.i64(i8* %4, i8* %5, i64 40, i32 1, i1 false) + %6 = bitcast %V* %3 to %swift.opaque* + ret %swift.opaque* %6 +} |
